Dual-fuel irrigation

Considering yearly fluctuations in energy prices, flexibility in fuel sources is a good thing for irrigators. Nebraska-based AmeriFuels Energy Solutions, one of the pioneers in marketing irrigation engines that run on ethanol, now has another option for irrigators — an engine that burns both ethanol and natural gas.

Mar 30, 2011

Dual-fuel irrigation

By DON McCABE

Considering yearly fluctuations in energy prices, flexibility in fuel sources is a good thing for irrigators. Nebraska-based AmeriFuels Energy Solutions, one of the pioneers in marketing irrigation engines that run on ethanol, now has another option for irrigators — an engine that burns both ethanol and natural gas.

AmeriFuels is a division of Renewable Fuels Technology of Kearney, founded by John Hanson and John McCoy of Kearney and Phil High of Bertrand. About 40 AmeriFuels spark-ignition, dual-fuel engines were operating in 2010, and the majority burned at least 10% to 15% ethanol with the natural gas. The ratio can be adjusted depending on field application and the irrigator’s preference.

At a glance

• AmeriFuels is marketing an ethanol-natural gas engine.

• Company also markets 98% ethanol engine for irrigators.

• Natural gas price is about half the price of ethanol this year.

Fifty engines, under the company’s initial program two years ago, continue running on 98% ethanol.

“This year, natural gas is half the price of ethanol,” says Marv Crawford, head of sales and service for AmeriFuels. “Three years ago, ethanol was cheaper.”

It’s a simple matter of economics for Hanson, who this season converted an AmeriFuels 8.1-liter engine that previously ran on 98% ethanol to the dual-fuel engine at 26% ethanol, 74% natural gas. While he’s yet to pencil in this summer’s irrigation fuel bill, he thinks it will be at least 25% lower than in 2009.

The same engine platform — an 8.1-liter GM engine that the company modified to run on 98% ethanol — is used in the dual-fuel system. Port injectors electronically inject both the natural gas and ethanol into the engine at the desired blend preset on a computer module, the key component in their system.

“We’re giving farmers the flexibility of switching from ethanol to the ethanol-natural gas blend,” says Hanson. “If natural gas prices go back up, we can switch back to ethanol.”

Blending in ethanol, according to Crawford, makes the engine run more efficiently by providing more torque and horsepower and lowering operating temperature.

The AmeriFuels pure ethanol engine is part of a closed-loop package for customers that includes an ethanol storage tank and a contract to purchase ethanol and have it delivered to the farm. The company contracts with about a half-dozen ethanol plants for the ethanol.

HYBriD ENGINE: Marv Crawford of AmeriFuels says natural gas is a low-price irrigation engine fuel, and blending ethanol in the engine helps it run more efficiently.

This article published in the December, 2010 edition of NEBRASKA FARMER.